Deposition processes such as, for example, chemical vapor deposition and atomic layer deposition processes, are used in one or more steps during the manufacture of a semiconductor device to form one or more films or coatings on the surface of a substrate. In a typical CVD or ALD process, a precursor source that may be in a solid and/or liquid phase is conveyed to a reaction chamber having one of more substrates contained therein where the precursor reacts under certain conditions such as temperature or pressure to form the coating or film on the substrate surface.
When a solid precursor material is used in a CVD or ALD process, the precursor material is typically heated in a separate chamber such as an oven to a temperature sufficient to form a gas, which is then transported, typically in conjunction with a carrier gas, to the reaction chamber. In some instances, the solid precursor material is heated to its gaseous phase without forming an intermediate liquid phase. The vaporization of a solid precursor material presents difficulties in generating and conveying the precursor-containing vapor to the reaction chambers. Typical difficulties encountered include, but are not limited to, deposit buildup within the vessel, vaporizer and/or delivery lines; condensation of liquid- or solid-phase material within the vessel, vaporizer and/or delivery lines, formation of “cold spots” within the interior of the vessel; and inconsistent vapor flow to downstream reaction chambers. These difficulties may result in extended “down time” of the production equipment to remove liquid or particulate matter and may also produce relatively poor quality deposited films.